The video above shows how the modded arcade stick works with a PS Vita playing UMvC3--albeit with some fairly visible input lag. But, hey, this is a pretty good first attempt, and it also works with the stick’s auto-fire feature. Whether you want to sacrifice the PS Vita’s portability or awkwardly carry around a peripheral that is significantly larger than the system itself is up to you, though.

The modder didn't leave any information as to how they made it work beyond providing a single image of the PS Vita connected to an additional logic board, which I assume itranslates the inputs from the arcade stick to the PS Vita.